gridtext.c

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/*	Terminate finished line for printing
*/
    previous->data[previous->size] = 0;

/*	Align left, right or center
*/

    spare =  (int) (HTScreenWidth - style->rightIndent + style->leftIndent -
		    previous->size);		     /* @@ first line indent */
		
    switch (style->alignment) {
	case HT_CENTER :
	    previous->offset = previous->offset + indent + spare/2;
	    break;
	case HT_RIGHT :
	    previous->offset = previous->offset + indent + spare;
	    break;
	case HT_LEFT :
	case HT_JUSTIFY :		/* Not implemented */
	default:
	    previous->offset = previous->offset + indent;
	    break;
    } /* switch */

    text->chars = text->chars + previous->size + 1;	/* 1 for the line */
    text->in_line_1 = NO;		/* unless caller sets it otherwise */
    
/*	If displaying as we go, output it:
*/
    if (text->display_on_the_fly) {
        if (text->display_on_the_fly == DISPLAY_LINES) { /* First line */
	    if (previous->size == 0) {
	        text->top_of_screen++;	/* Scroll white space off top */
		return;
	    }
	    if (HTAnchor_title(text->node_anchor)) { /* Title exists */
	        display_title(text);
	        text->display_on_the_fly--;
	    }
	}
	display_line(text, previous);
	text->display_on_the_fly--;
	
	/* Loop to top of next page? */
	if (!text->display_on_the_fly && text->all_pages) {
	    PUTS("\f\n"); /* Form feed on its own line a la rfc1111 */
	    text->display_on_the_fly = DISPLAY_LINES;
	}
    }
} /* split_line */


/*	Allow vertical blank space
**	--------------------------
*/
PRIVATE void blank_lines (HText * text, int newlines)
{
    if (text->last_line->size == 0) {	/* No text on current line */
	HTLine * line = text->last_line->prev;
	while ((line!=text->last_line) && (line->size == 0)) {
	    if (newlines==0) break;
	    newlines--;		/* Don't bother: already blank */
	    line = line->prev;
	}
    } else {
	newlines++;			/* Need also to finish this line */
    }

    for(;newlines;newlines--) {
	new_line(text);
    }
    text->in_line_1 = YES;
}


/*	New paragraph in current style
**	------------------------------
** See also: setStyle.
*/

PUBLIC void HText_appendParagraph (HText * text)
{
    int after = (int) text->style->spaceAfter;
    int before = (int) text->style->spaceBefore;
    blank_lines(text, after>before ? after : before);
}


/*	Set Style
**	---------
**
**	Does not filter unnecessary style changes.
*/
PUBLIC void HText_setStyle (HText * text, HTStyle * style)
{
    int after, before;

    if (!style) return;				/* Safety */
    after = (int) text->style->spaceAfter;
    before = (int) style->spaceBefore;
    HTTRACE(SGML_TRACE, "Rendering... Change to style %s\n" _ style->name);
    blank_lines (text, after>before ? after : before);
    text->style = style;
}


/*	Append a character to the text object
**	-------------------------------------
*/
PUBLIC void HText_appendCharacter (HText * text, char ch)
{
    HTLine * line = text->last_line;
    HTStyle * style = text->style;
    int indent = (int)(text->in_line_1 ? style->indent1st : style->leftIndent);
    
/*		New Line
*/
    if (ch == '\n') {
	    new_line(text);
	    text->in_line_1 = YES;	/* First line of new paragraph */
	    return;
    }

/* 		Tabs
*/

    if (ch == '\t') {
        HTTabStop * tab;
	int target;	/* Where to tab to */
	int here = line->size + line->offset +indent;
        if (style->tabs) {	/* Use tab table */
	    for (tab = style->tabs;
	    	tab->position <= here;
		tab++)
		if (!tab->position) {
		    new_line(text);
		    return;
		}
	    target = (int) tab->position;
	} else if (text->in_line_1) {	/* Use 2nd indent */
	    if (here >= style->leftIndent) {
	        new_line(text); /* wrap */
		return;
	    } else {
	        target = (int) style->leftIndent;
	    }
	} else {		/* Default tabs align with left indent mod 8 */
#ifdef DEFAULT_TABS_8
	    target = ((line->offset + line->size + 8) & (-8))
	    		+ style->leftIndent;
#else
	    new_line(text);
	    return;
#endif
	}
	if (target > HTScreenWidth - style->rightIndent) {
	    new_line(text);
	    return;
	} else {
            text->permissible_split = line->size;	/* Can split here */
	    if (line->size == 0) line->offset = line->offset + target - here;
	    else for(; here<target; here++) {
                line->data[line->size++] = ' ';	/* Put character into line */
	    }
	    return;
	}
	/*NOTREACHED*/
    } /* if tab */ 

    
    if (ch==' ') {
        text->permissible_split = line->size;	/* Can split here */
    }

/*	Check for end of line
*/    
    if (indent + line->offset + line->size + style->rightIndent
    		>= HTScreenWidth) {
        if (style->wordWrap) {
	    if(text->permissible_split > line->size)	/* HENRIK 21/02-94 */
		text->permissible_split = line->size;
	    split_line(text, text->permissible_split);
	    if (ch==' ') return;	/* Ignore space causing split */
	} else new_line(text);
    }

/*	Insert normal characters
*/
    if (ch == HT_NON_BREAK_SPACE) {
        ch = ' ';
    }
    {
        HTLine * line = text->last_line;	/* May have changed */
        HTFont font = style->font;
        line->data[line->size++] =	/* Put character into line */
           font & HT_CAPITALS ? TOUPPER(ch) : ch;
        if (font & HT_DOUBLE)		/* Do again if doubled */
            HText_appendCharacter(text, HT_NON_BREAK_SPACE);
	    /* NOT a permissible split */ 
    }
}

PUBLIC void HText_appendText (HText * text, const char * str)
{
    const char * p;
    for(p=str; *p; p++) {
        HText_appendCharacter(text, *p);
    }
}


PUBLIC void HText_endAppend (HText * text)
{
    new_line(text);
    
    if (text->display_on_the_fly) {		/* Not finished? */
        fill_screen(text, text->display_on_the_fly);	/* Finish it */
	text->display_on_the_fly = 0;
	text->next_line = text->last_line;	/* Bug fix after EvA 920117 */
	text->stale = NO;
    }
}

/*		Anchor handling
**		---------------
*/
/*	Start an anchor field
*/
PUBLIC void LMHText_beginAnchor (HText * text,
    int elem_num, int attr_num, HTChildAnchor * anc,
    const BOOL *present, const char **value)
{
    TextAnchor * a;

			/* this is because it's called as link callback */
    if (elem_num != HTML_A)
	return;

    if ((a = (TextAnchor  *) HT_MALLOC(sizeof(*a))) == NULL)
        HT_OUTOFMEM("HText_beginAnchor");
    a->start = text->chars + text->last_line->size;
    a->extent = 0;
    if (text->last_anchor) {
        text->last_anchor->next = a;
    } else {
        text->first_anchor = a;
    }
    a->next = 0;
    a->anchor = anc;
    text->last_anchor = a;
     text->current_anchor = a;
    
    if (HTAnchor_followMainLink((HTAnchor*)anc)) {
        a->number = ++(text->last_anchor_number);
    } else {
        a->number = 0;
    }
}


PUBLIC void LMHText_endAnchor (HText * text)
{
    TextAnchor * a = text->current_anchor;
    char marker[100];

    if (!a)			/* </A> without <A> */
	return;

    if (a->number && display_anchors) {	 /* If it goes somewhere */
	sprintf(marker, end_reference, a->number);
	HText_appendText(text, marker);
    }
    a->extent = text->chars + text->last_line->size - a->start;
    text->current_anchor = 0;
}


/* LMHText_addText() satisfies HText callback requirement.  */
PUBLIC void LMHText_addText (HText * text, const char * str, int length)
{
    const char * p;
    int i;
    for (i=0,p=str; i<length; ++i,++p) {
        HText_appendCharacter(text, *p);
    }
}

/*		IMAGES
*/
PUBLIC void HText_appendImage (
	HText * 		text,
	HTChildAnchor * 	anc,
	const char * 		alt,
	const char *  		alignment,
	BOOL			isMap)
{
    HText_appendText(text, alt? alt : "[IMAGE]");
}

PUBLIC void HText_appendObject (HText * text, int element_number,
	                        const BOOL * present, const char ** value)
{
}

PUBLIC void HText_appendLink (HText * text, HTChildAnchor * anchor,
			      const BOOL * present, const char ** value)
{
}

/*	Return the anchor associated with this node
*/
PUBLIC HTParentAnchor * HText_nodeAnchor (HText * text)
{
    return text->node_anchor;
}

/*				GridText specials
**				=================
*/
/*	Return the anchor with index N
**
**	The index corresponds to the number we print in the anchor.
*/
PUBLIC HTChildAnchor * HText_childNumber (HText * text, int number)
{
    TextAnchor * a;
    for (a = text->first_anchor; a; a = a->next) {
        if (a->number == number) return a->anchor;
    }
    return (HTChildAnchor *)0;	/* Fail */
}

PUBLIC void HText_setStale (HText * text)
{
    if (text)
	text->stale = YES;
}

PUBLIC void HText_refresh (HText * text)
{
    if (text && text->stale)
	display_page(text, text->top_of_screen);
}

PUBLIC int HText_sourceAnchors (HText * text)
{
    return (text ? text->last_anchor_number : -1);
}

PUBLIC BOOL HText_canScrollUp (HText * text)
{
    return (text && text->top_of_screen != 0);
}

PUBLIC BOOL HText_canScrollDown (HText * text)
{
    return (text && (text->top_of_screen + DISPLAY_LINES -
		     (text->title ? TITLE_LINES : 0)) < text->lines);
}

/*		Scroll actions
*/
PUBLIC void HText_scrollTop (HText * text)
{
    display_page(text, 0);
}

PUBLIC void HText_scrollDown (HText * text)
{
    display_page(text, text->top_of_screen + DISPLAY_LINES -1);
}

PUBLIC void HText_scrollUp (HText * text)
{
    display_page(text, text->top_of_screen - DISPLAY_LINES +1);
}

PUBLIC void HText_scrollBottom (HText * text)
{
    display_page(text, text->lines - DISPLAY_LINES +1);
}


/*		Browsing functions
**		==================
*/

/* Bring to front and highlight it
*/

PRIVATE int line_for_char (HText * text, int char_num)
{
    int line_number =0;
    int characters = 0;
    HTLine * line = text->last_line->next;
    for(;;) {
	if (line == text->last_line) return 0;	/* Invalid */
        characters = characters + line->size + 1;
	if (characters > char_num) return line_number;
	line_number ++;
	line = line->next;
    }
}

PUBLIC BOOL HText_select (HText * text)
{
    if (text) {
        HTMainText = text;
	HTMainAnchor = text->node_anchor;
	display_page(text, text->top_of_screen);
	return YES;
    }
    HTTRACE(SGML_TRACE, "Rendering... Nothing to select!\n");
    return NO;
}

PUBLIC BOOL HText_selectAnchor (HText * text, HTChildAnchor * anchor)
{
    TextAnchor * a;

    for(a=text->first_anchor; a; a=a->next) {
        if (a->anchor == anchor) break;
    }
    if (!a) {
        HTTRACE(SGML_TRACE, "Rendering... No such anchor in this text!\n");
        return NO;
    }

    if (text != HTMainText) {		/* Comment out by ??? */
        HTMainText = text;		/* Put back in by tbl 921208 */
	HTMainAnchor = text->node_anchor;
    }

    {
	int l = line_for_char(text, a->start);
	HTTRACE(SGML_TRACE, "Rendering... Selecting anchor [%d] at char %d, line %d\n" _ 
		    a->number _ a->start _ l);

	if ( !text->stale &&
	    (l >= text->top_of_screen) &&
	    ( l < text->top_of_screen + DISPLAY_LINES-1))
	    return YES;
        display_page(text, l - (DISPLAY_LINES/3));	/* Scroll to it */
    }
    return YES;
}
 

/*		Editing functions		- NOT IMPLEMENTED
**		=================
**
**	These are called from the application. There are many more functions
**	not included here from the orginal text object.
*/

/*	Style handling:
*/
/*	Apply this style to the selection
*/
PUBLIC void HText_applyStyle (HText *  me, HTStyle * style)
{
    
}


/*	Update all text with changed style.
*/
PUBLIC void HText_updateStyle (HText *  me, HTStyle * style)
{
    
}


/*	Return style of  selection
*/
PUBLIC HTStyle * HText_selectionStyle (
	HText * me,
	HTStyleSheet * sheet)
{
    return 0;
}


/*	Paste in styled text
*/
PUBLIC void HText_replaceSel (
	HText * me,
	const char * aString, 
	HTStyle * aStyle)
{
}


/*	Apply this style to the selection and all similarly formatted text
**	(style recovery only)
*/
PUBLIC void HTextApplyToSimilar (HText * me, HTStyle * style)
{
    
}

 
/*	Select the first unstyled run.
**	(style recovery only)
*/
PUBLIC void HTextSelectUnstyled (HText * me, HTStyleSheet * sheet)
{
    
}


/*	Anchor handling:
*/
PUBLIC void		HText_unlinkSelection (HText * me)
{
    
}

PUBLIC HTAnchor *	HText_referenceSelected (HText * me)
{
     return 0;   
}


#ifdef CURSES
PUBLIC int HText_getTopOfScreen (HText * text)
{
      return text->top_of_screen;
}

PUBLIC int HText_getLines (HText * text)
{
      return text->lines;
}
#endif
PUBLIC HTAnchor *	HText_linkSelTo (HText * me, HTAnchor * anchor)
{
    return 0;
}

/*	HTML callback functions
*/
PUBLIC void LMHText_beginElement (HText * text,
    int elem_num, const BOOL * present, const char ** value)
{
    return;
}

PUBLIC void LMHText_endElement (HText * text, int elem_num)
{
    switch (elem_num) {
    case HTML_A:
	LMHText_endAnchor (text);
	break;
    default:
	break;
    }
    return;   
}